/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.netease.spark.utils;

import java.io.InputStream;
import java.util.Properties;

public class JConfig {
  private static Properties properties = null;
  private static String PROPERTIES_RESOURCE_FILE_NAME = "conf.properties";

  public static Properties getInstance() {
    if (properties == null) {
      synchronized(JConfig.class) {
        if (properties == null) {
          try {
            if (Utils.checkFileExists("./conf/conf.properties")) {
              properties = Utils.getPropertiesFromPath("./conf/conf.properties");
            } else if (Utils.checkFileExists("./conf.properties")) {
              properties = Utils.getPropertiesFromPath("./conf.properties");
            } else {
              ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
              InputStream inputStream = classLoader.getResourceAsStream(PROPERTIES_RESOURCE_FILE_NAME);
              properties = new Properties();
              properties.load(inputStream);
            }
          } catch (Exception e) {
            throw new RuntimeException("Resource properties load failed:", e);
          }
        }
      }
    }

    return properties;
  }
}
